Title:
鍛造クランク軸の製造方法
Document Type and Number:
Japanese Patent JP6658916
Kind Code:
B2
Abstract:
A production method includes a preforming process, a forming process and a finish forging process. In the preforming process, an intermediate preform (24) is formed from a billet. In the forming process, while each of a plurality of rough journals (24j) of the intermediate preform is held and pressed vertically by a pair of holding dies (60), rough pins (24p) are decentered in directions perpendicular to the pressing direction by the holding dies (60) and an axial direction of the intermediate preform (24), and the intermediate preform (24) is pressed in the axial direction of the intermediate preform (24). In the finish forging process, a final preform (25) is placed such that the directions in which the rough pins (24p) are decentered are parallel to a horizontal direction, and the thus placed final preform (25) is pressed vertically by a pair of pressing dies, whereby a finish-forged product (26) including a plurality of journals (J), a plurality of pins (P) and a plurality of crankarms (A) is formed. The production method reduces the risk of occurrence of seams on a forged crankshaft.
Inventors:
Junichi Okubo
Kenji Tamura
Kunihiro Yoshida
Huang Sanmori
Nakano Ryusuke
Masao Hori
Kenji Tamura
Kunihiro Yoshida
Huang Sanmori
Nakano Ryusuke
Masao Hori
Application Number:
JP2018553658A
Publication Date:
March 04, 2020
Filing Date:
August 24, 2017
Export Citation:
Assignee:
Nippon Steel Corporation
International Classes:
B21K1/08; B21J5/02; B21J13/02
Domestic Patent References:
| JP2011078995A | ||||
| JP2000094087A | ||||
| JP2012161819A |
Foreign References:
| WO2016152933A1 | ||||
| WO2014038183A1 |
Attorney, Agent or Firm:
Ascend Patent Business Corporation